The Propagation of Dwarf Japanese Garden Juniper

The fine needles of dwarf Japanese garden juniper make it excellent for Bonsai.

Dwarf Japanese Garden Juniper (Juniperus procumbens 'Nana') is one of the most popular low growing junipers. It grows best in United States Department of Agriculture plant hardiness zones 4 to 9. Plant in well-drained soil in full sun. Once established it can tolerate drought, wind and salt spray. It will grow 1 foot tall and spread to 3 or 4 feet. It can be propagated by stem layering or cuttings.

Transplanting Rooted Branches

Dwarf Japanese garden juniper grows along the ground, forming dense mats of foliage with branches on top of each other. Most mature specimens will have roots along the underside of the lowest branches. Push aside the upper branches and lift some of the lower branches to determine if roots have developed. If they have, the branch can be cut and transplanted to a new location. If the roots are there but are underdeveloped cover the branch with soil to promote root development.

Stem Layering

Roots can be forced to develop on stems by stem layering. Select a healthy branch to layer. Remove mulch and debris from under the branch, exposing bare soil. Scrape the bark off the lower part of the branch for 6 inches, starting about 10 inches from the tip of the branch. Pin the scraped section to the ground using a landscape pin and cover it with soil, leaving the tip exposed. Keep the soil moist but not soggy. Let the roots develop until they are able to hold a soil ball together then transplant the new juniper.

Cuttings

Junipers can also be propagated from cuttings. Cut 4 to 8 inches from the tip of several branches in the fall. Snip off growth from the lower 1 1/2 to 2 inches. Dip this end in rooting powder. Make holes in sterile rooting medium, stick the cuttings in the holes and press the rooting medium around them. Water the medium to settle the soil around the cuttings and cover the propagation tray. It may take a few months for the cuttings to form roots. Transplant them to pots when the roots are about 3 inches long.

Seed

The dwarf Japanese garden juniper seldom produces berries. Any berries it produces may be sterile. Berries should be cold stratified by keeping them in the refrigerator in moist sphagnum moss for 3 months before planting. After planting they may take two to three months to sprout if they are not sterile. When they do sprout they are likely to have different qualities than the dwarf Japanese garden juniper, because they are hybrids. Seed propagation is not recommended unless you are trying to develop new juniper varieties.

About the Author

Lynn Doxon has a Ph.D. in horticulture, is a retired cooperative extension specialist and teaches courses in urban farming. She is the author of three books: "The Alcohol Fuel Handbook," "High Desert Yards and Gardens" and "Rainbows from Heaven." Doxon wrote the Yard and Garden column for the "Albuquerque Journal" and numerous magazine and newspaper articles and cooperative extension service guides.